As a process for producing display panel for flat panel display such as plasma display panel, there has been known a technique of providing a thin film for a transparent electrode on a glass substrate, and irradiating the thin film for transparent electrode with a laser beam to conduct patterning, thus forming a transparent electrode (see, for example, patent documents 1 and 2). According to such processing method utilizing laser beam, the number of production steps can be decreased in comparison with the photo lithography steps and, further, necessity of preparing a large-sized photo mask is eliminated. Still further, the production line is made more compact, which serves to reduce the land area necessary for the process, thus the step number being decreased and the process being stabilized.    Patent document 1: JP-A-2001-52602    Patent document 2: JP-A-2005-108668